1. Field of the Invention
The invention relates to a method and an apparatus for positioning a train, comprising a locomotive and a plurality of cars, which are coupled via pulling and pushing devices, with the interposition of spring forces. In particular, it relates to the use of freight cars in rail transport and the relative arrangement of such cars relative to predetermined stopping points or markings along a platform edge.
2. Description of the Related Art
The necessary accuracy of the positioning of the cars of a train depends on the method of loading and the nature of the freight. Thus, for example, in order to load cars with bulk material, it is sufficient to position the cars by eye. If, on the other hand, trucks or wheeled containers or other wheeled or track vehicles have to be run from platforms to the cars, or vice versa, transversely to the rails, it is necessary in certain cases to position the individual cars with tolerances of less than 10 cm in each case. This positioning is generally done by eye and with repeated correction by the personnel, working with the train driver.
According to the prior art, freight cars are positioned by manual shunting of the cars with a locomotive or shunting locomotive, using manual operation of the train""s brakes. Buffers and brake shoes are also employed in sidings. No comparatively simple, substantially mechanical method or similar device for the automated positioning of all cars of the train, and hence of the train as a whole, is yet in use.
It is an object of the invention to provide a method and an apparatus of the type referred to initially by means of which it is possible to position all cars of the train with tolerances of, for example, less than 10 cm relative to a predetermined stationary marking, in order thus to enable automation of the operations of loading and unloading the cars, since such automation is dependent on such a degree of accuracy.
This object is achieved, according to the invention, in that a first end of the train is previously positioned and a stop device is activated, in that the train is moved until the stop device interacts with a counter-stop, a force acting in the longitudinal direction of the train being applied, and is further elastically lengthened or shortened by utilizing the spring forces, in that a further stop device is activated at a second end of the train, and in that the force acting in the longitudinal direction is reduced and the train is moved under the influence of the spring forces against the direction in which the change of length is effected until the further activated stop device interacts with a further counter-stop, an elastic prestress being maintained.
The invention exploits the elastic lengthening and shortening of the train, which become possible as a result of pulling and pushing devices connected to the train via springs. The basic positioning of the train or chain of cars at equal intervals is achieved, by virtue of the defined, in other words stationary, arrangement of the two stop devices, with great accuracy, down to less than 1 cm, so that subsequently each individual car is positioned with an accuracy down to less than 5 cm. This arises as a result of the fixed tensioning of the train at both its ends via the stops and counter-stops provided there which is provided according to the invention. The accuracy here is independent of the thermal expansion of the train. The force acting in the longitudinal direction of the train an be a tractive or compressive force, which is exercised primarily by the locomotive. It may however also be applied, in whole or in part, by a separate mechanical installation, for example via an electromechanically or hydraulically actuated piston/cylinder arrangement provided in the track bed.
The invention also relates to an apparatus for carrying out the method according to the invention. This is characterized in that one stop device is provided at least in the region of the two ends of the train, these stop devices interacting in the event of activation with one stationary counter-stop or one counter-stop arranged on the train in each case. If the counter-stops are arranged on the train, the stop devices are provided so as to be stationary. If, however, the stop devices are arranged on the train, the counter-stops for their part are arranged to be stationary.
According to the invention, each stop device has an extendable, in other words activatable, bolt which interacts with the counter-stop assigned to it. The latter is preferably provided with a damping device, which exerts its damping effect when the bolt impacts the stop device.
Further details, features and advantages of the invention are apparent from the description of a plurality of preferred examples of embodiment that follows and from reference to the diagrammatic drawing and the patent claims.
In the drawing:
FIG. 1 shows a lateral view of a freight train comprising a plurality of cars,
FIG. 2 shows an enlarged illustration of the free end of the left-hand freight car according to FIG. 1, to illustrate the positioning device with a stationary counter-stop according to the invention,
FIG. 3 shows a similar view to FIG. 2 with a counter-stop provided on a car, and
FIG. 4 shows a train with a counter-stop additionally provided, for example, at the center of the train.